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another way of dealing with passenger side engine bay harnesses
you know how we hate that harness on the passenger side? i really dont like the idea of having wires in the wheel well which most have done to eliminate engine bay clutter.
so i currently have the engine out and since i deleted abs, i wanted to get ride of all the abs/tcs wires from this thing. the main reason was to get rid of the EBCM harness/block that was left over and just laying there by the fuse box. so i figured why not strip the loom, get rid of all the wires, then replace with new loom. this isn't anything new. so i traced all the wires, removed the module from under the steering wheel, pulled all those wires, as well as chasing all the wires that run up along the passenger side of the engine bay. i think there were 4, TPS sensor info for the EBCM and i forget what the other few were. i also will be removing all the ac wires, which im learning there are more than i thought which is a good thing. also will be doing the secondary air, relocating rear o2 wires, removing egr etc.
so im realizing that a few ac wires also go along the passenger side. so now im thinking, what can we do with these connectors that now only have 4-5 wires going to them? i could resplice them al, extend a few etc and now only have 2 connectors. but then i thought, the only time these connectors need to be removed is when the motor comes out, and hopefully we wont ever have to do that.......so why not eliminate the connectors? after i remove the rest of the unneeded wires, i can mock up the engine harness to simulate approximately where the harness will be or just wait until the motor is back in to do this, but i will just one by one cut and sauter (spell check) the wires to make 1 harness and 1 loom on the passenger side eliminating the 4 connectors that are there. i figure i could also fill the holes from the connector clips in the fender and leave 1 open for the loom holder, which if im lucky i can squeeze them all in 1/2" loom but will most likely need the 3/4". also at least half the wires go into the pcm right away, so no real issues with adding a ton of wire......thoughts? i have a repair manual with all the pinouts, and im not sure how soon i can accomplish this with a lot else going on but will try to keep it updated. this would be a big job for those with abs/tcs and AC still, but for those who dont maybe give it a try.
so my car is a 2000, and the manual is for a 1999, but everything is the same from 99-02. when i try to find online images of the connector pinouts to post on here so you guys can see what im doing, when i compare them to the manual the wording on a lot of them is different. some polar opposites. but ill post up the cd rom assuming that these are 100% accurate
my only issue is i cant for the life of me find pinouts for C102
you can see what i mean about comparing wording from this site
so not counting inside this mystery C102 that i will just have to trace back to see where it goes, im counting 7 wires in C105, 9 in C101, and 9 in C100. NW9 is the RPO code TCS
from C105 i can lose A,C,D(i dont think i have this) F (also dont think i have this) G (this is tach signal TO the EBCM NW9) and H so i only need 1 wire in this entire connector
from C101, I can only lose K (NW9) i believe, so i need 8 from here. (EDIT, i found out later when i was double checking everything that i could have eliminated J from here. looks like this is for an automatic sending a signal to the PCM to say its in N or P to allow the engine crank. Im an M6 and found this out when i looked at the PCM harness and `saw J was unused with a plug in it. wasted time lengthening this wire)
from C100, i can lose B, C, D (NW9), E (NW9) and K (NW9)
anything that says NW9 i will have to double check the wiring diagrams to be sure they are in fact for traction control and not something else. as mentioned i already followed all the wires from the EBCM and pulled those so most if not all of these NW9 should be gone, but i dont remember pulling that many from the passenger side.
if all these are correct, i will go from 25 wires down to 13, so i would need to solder 13 together.
Last edited by Floorman279; 03-03-2019 at 12:53 PM.
Reason: .....
There are molex 16 pin connectors that would let you run all the circuits through just 1 plug. You just have to make sure it's a sealed version that can handle the power level your wires are running. You don't want to run a fused 25 circuit through a connector that's limited to 18.
There are molex 16 pin connectors that would let you run all the circuits through just 1 plug. You just have to make sure it's a sealed version that can handle the power level your wires are running. You don't want to run a fused 25 circuit through a connector that's limited to 18.
i might look into that....honestly i got to thinking again, and what i could do is just reroute the wires coming from the pcm, and run them behind it. then extend the wires i need, add the connectors, and now those connectors would fit behind the pcm. and then just add them all into one loom......i like that idea better.
and i get the wheel mod, but as dumb as it sounds, i would constantly be looking underneath at it and thinking how ugly it is to see those wires.
???? But it's between plastic fender well and metal portion of the fender...you can't see it once finished
yea but i know if i look under there its there lol....again, you never know when you will get caught in the rain even in a once a week car, you may never know when you may not be paying attention and you run over a piece of truck tire and it kicks up inside the well or something....just not a fan despite knowing it will probably be fine.
I honestly thought you were confused on it sorry man. To be fair I don't have the connectors anymore, I moved my coils after doing a battery delete so that's what I ran there not the oe connectors. I'm in a similar boat where abs is gone and since I have a stand alone harness and fan control box a lot of the driver side bay wiring needs to go. I'm interested to see what you come up with.
Now that I think of it, I might just run it through the drivers side and under the dash. Then just come out behind the pcm. Then there will be no wires on the pass side. The only shitty thing is I just finished painting my engine bay. Now I'm goona want to fill the holes sand and repaint that section
yea but i know if i look under there its there lol....again, you never know when you will get caught in the rain even in a once a week car, you may never know when you may not be paying attention and you run over a piece of truck tire and it kicks up inside the well or something....just not a fan despite knowing it will probably be fine.
got a chance to start working on this.....one speed bump, forgot about the HVAC vacuum thing that is by the horns on the pass side. so now it looks like i will have to run 12 feet of vacuum line along the rad support though the firewall by the booster and wrap it all around under the dash to the port by the PCM. hopefully that long *** line will still allow the vents to operate proper.
got it all done, still need to hang the wire under the steering column but other than that all is good. i basically opened up the loom along the radiator support. i determined which wires weren't needed based off of my post earlier, and back traced those wires and cut them or pulled them from their connectors on both sides. once i was left with all the wires i still needed, i wrote down the wire color and their position in the connectors before removing them from the connector. i also taped the wires that went to C101 together as well as C100 since the wire colors duplicated. that solo wire pink wire from C105 got taped with the C100 because later i was goona add it to that connector (i also swapped it in the PCM harness as well now to prevent forgetting) i didn't wanna deal with labeling each wire cause i knew the tape would get torn at some point especially when feeding through the firewall so this method seemed easiest.
once i got the giant harness secured to the firewall, i then cut off all the wire pins and retaped to keep them paired. i then soldered longer wires onto all those ends and determined how long the wires needed to be, then cut and reattached those pins to the correct wires. i then ran them though the firewall hole on the passenger side where those 2 connectors run to the pcm, those 2 that you need to remove the kick panel to get to. from there i just put the pins into the correct connector locations, and added the wire loom to protect it all inside. also ran the vacuum tubing for the HVAC as well. sounds short but a lot of wire stripping and soldering this took a lot of time since i wanted to take my time not to mess anything up.....hopefully. the only small catch is that grommet that goes in the passenger side firewall, that has to be cut so i can slide it around the new wire loom when the engine harness goes back in the car, and now may add a minimal amount of wind noise.
yea the only reason i did this was cause the engine was out and i was painting. also because i busted open the loom to delete abs wires. would i do it again......lol who knows. i hopefully m keeping this for awhile.
02-12-2019, 08:07 PM
another way of dealing with passenger side engine bay harnesses 
